Solid composite propellants containing diamine dinitrates



United States Patent 3,024,144 SOLID COMPOSITE PROPELLANTS CONTAINING DIAMINE DINITRATES George D. Sammons, Bartlesville, Okla, assignor to Phillips Petroleum Company, a corporation of Delaware No Drawing. Filed Dec. 29, 1958, Ser. No. 783,617 18 Claims. (Cl. 149-19) This invention relates to solid propellant compositions. In one aspect this invention relates to solid propellant compositions containing a burning rate depressing agent. In another aspect this invention relates to incorporating certain selected diamine dinitrates in certain solid propellants.

Solid propellants can be classified with respect to composition as double base type, single base type, and composite type. An example of a double base propellant is ballistite which comprises essentially nitroglycerine and nitrocellulose. Examples of single base propellants are nitrocellulose and trinitrotoluene. Composite type propellants are generally composed of an oxidizer, and a binder or fuel. Said composite type propellants may contain other materials to facilitate manufacture or increase ballistic performance such as a burning rate catalyst.

Rocket propellants have achieved considerable commercial importance as Well as military importance. Jet propulsion motors of the type in which the propellants of this invention are applicable can be employed to aid a heavily loaded plane in take off. Said motors can also be employed as an auxiliary to the conventional power plant when an extra surge of power is required. Said motors can also be employed to propel projectiles and land vehicles. Said propellants can also be used for uses other than propulsion. For example, they can be used as gas generators in starting devices, power units where a fluid is employed as a motive force, and other applications where a comparatively large volume of gas is required in a relatively short period of time.

Recently, it has been discovered that superior solid propellant materials are obtained comprising a solid oxidant such as ammonium nitrate or ammonium perchlorate, and a rubbery material such as a copolymerof butadiene and a vinylpyridiue or other substituted heterocyclic nitrogen base compound, which after incorporation is cured by a quaternization reaction or a vulcanization reaction. Solid propellant mixtures of this nature and a process for their production are disclosed and claimed in copending application Serial No. 284,447, filed April 25, 1952, by W. B. Reynolds and J. E. Pritchard.

In the utilization of solid composite type propellant compositions, it is important to control the burning rate and thus be able to control the amount of thrust developed per unit of time for a given charge of propellant. In many instances burning rate catalysts are utilized to increase the burning rate. However, with some oxidizers, e.g., ammonium perchlorate and the alkali metal perchlorates, it is desirable in many instances to depress the burning rate. Said perchlorate propellants have many desirable properties, particularly a high specific impulse, and frequently are satisfactory from every standpoint except burning rate.

I have discovered that the burning rate of composite type solid propellants wherein salts of perchloric acid are used as the oxidizer component can be decreased by incorporating in the propellant composition one or more diamine dinitrates as described herein.

Thus, broadly speaking, the present invention resides in propellant compositions comprising a perchlorate oxidizer component, a binder component, and a selected diamine dinitrate as defined further hereinafter.

An object of this invention is to provide an improved propellant composition. Another object of this invention is to provide a burning rate depressing agent for use in solid perchlorate containing propellants. Still another object of this invention is to provide a solid perchlorate containing propellant composition having a burning rate depressing agent incorporated therein. Other aspects, objects, and advantages of the invention will be apparent to those skilled in the art in view of this disclosure.

Thus, according to the invention there is provided a propellant composition comprised of: a base propellant comprising an oxidizer component selected from the group consisting of ammonium perchlorate and the alkali metal perchlorates, a binder component comprising av rubbery material selected from the group consisting of natural rubber and synthetic rubbery polymers and mixtures thereof; and from 0.1 to 20 parts by weight per parts by weight of said base propellant of a diamine dinitrate characterized by the structural formula at t/ A k R N0 N0 R wherein: R is an alkylene or alkenylene group containing from 2 to 14 carbon atoms; R is an alkyl group containing from'l to 4 carbon atoms, Which alkyl groups can be alike and unlike; and wherein the total number of carbon atoms in the molecule does not exceed 18.

Said diamine dinitrates are elfective at low concentrations, are compatible with other propellant ingredients, are stable under the conditions of use, and do not leave any undesirable residue upon burning. The action of said diamine dinitrates in depressing the burning rate is believed to be unique for said perchlorate containing proellants. For example, in copending application Serial No. 735,907, filed May 16, 1958, of which I am a coinventor, it is disclosed and claimed that many of the above defined diamine dinitrates increase the burning rate of composite type propellants containing ammonium nitrate and/ or an alkali metal nitrate as the oxidizer component. Furthermore, said diamine dinitrates in said copending application also serve as a processing aid in that they facilitate mixing and increase the extrudability of high oxidizer content nitrate containing propellants. Qualitative tests have shown that the above defined diamine dinitrates do not facilitate the processing of perchlorate containing propellants.

Representative diamine dinitrates which can be used in the practice of the invention include, among others, the following:

N,N,N',N-tetramethyl-2,B-diaminobutane dinitrate; N,N,N,N-tetramethyl-3,4-diaminohexane dinitrate; N,N,N',N-tetramethyl-1,2-diaminoethane dinitrate; N,N,N',N'-tetramethyl-1,3-diaminopropane dinitrate; N,N,N,N-tetramethyl-1,4-diaminopropane dinitrate; N,N,N',N-tetramethyl-1,6-diaminohexane dinitrate; N,N,N,N tetramethyl-l,3-diamino-2,Z-dimethylpropane dinitrate; N,N,N,N-tetramethyl 1,3 dianfino-Z-ethylpropane dinitrate; N,N,N,N-tetramethyl-2,4-diaminooctane dinitrate; N,N,N',N'-tetramethyl-1,3-diaminobutane dinitrate; N,N,N,N'-tetramethyl-1,4-diaminobutane dinitrate; N,N,N',N-tetramethyl-2,S-diaminohexane dinitrate;

N,N,N',N'-tetraethyl-1,3-diaminobutane dinitrate; N,N,N,N'-tetramethyl-1,4-diaminobutene-2 dinitrate; N,N-dimethyl-N,N'-diethyl-1,3-diaminobutane dinitrate; N,N,N,N-tetramethyl-1,5-diaminotetradecane dinitrate; N,N,N,N-tetra-n-propyl-1,3-diaminobutane dinitrate; N,N,N,N'-tetraethyl-l,3-diaminodecene-2 dinitrate; N,N,N,N-tetra-iso-propyl-1,4-diaminobutane dinitrate; N,N,N',N tetramethyl-1,5-diamino-2,4-dimethylpentane dinitrate; N,N,N',N-tetramethyl-l,8-diamino-3,6-dipropyl0ctane dinitrate;

N,N-dimethyl-N,N' diethyl-l,l-diatnino-2,8-dimethyldecane dinitrate;

N,N,N',N-tetramethyl-1,8-diaminooctane dinitrate; N,N,N,N-tetramethyl-1,14-diaminotetradecane dinitrate; N,N,N',N'-tetraethyl-1,2-diaminoethylene dinitrate; N,N,N,N-tetramethyl-1,3-diarninododecene-1 dinitrate;

and

l,l-bis(dimethylamino) ethane.

The amine nitrates employed in the practice of the invention can be prepared by several methods. One method is to react a suitable amine with nitric acid. Another method which can be employed is to form a salt of the amine such as a hydrochloride or an acetate, and then react the amine salt with nitric acid.

The quantity of the diamine dinitrate employed can be in the range of about 0.1 to about 20 parts by weight per 100 parts by weight of the base propellant. Usually, amounts in the range of 0.1 to 10 parts by weight per 100 parts by weight of base propellant are preferred, and amounts in the range of 0.2 to parts are more preferred. As used herein and in the claims unless otherwise specified, the term base propellant is defined as the binder component plus the oxidant component. The rubbery material employed in the binder component of the propellant compositions of the invention can be a natural rubber, a synthetic rubbery polymer, or a mixture of natural rubber and said rubbery polymer. The term rubbery polymer as used herein and in the claims, unless otherwise specified, is defined as including all rubbery polymers of olefins and diolefins which are prepared by either mass or emulsion polymerization. Some examples of suitable rubbery polymers are polybutadiene, polyisobutylene, polyisoprcne, copolymers of isobutylene and isoprene, copolymers of conjugated dienes with comonomers such as styrene, and copolymers of conjugated dienes with polymerizable heterocyclic nitrogen bases. Said copolymers of conjugated dienes with polymerizable heterocyclic bases comprise a preferred class of rubbery polymers for use in the binder component of the propellants of the invention. A presently preferred rubbery polymer is a copolymer of 1,3-butadiene with 2-methyl-5-vinyl- 2-vinylpyridine;

Said preferred class of rubbery polymers prepared by copolymerizing a conjugated diene with a heterocyclic nitrogen base can vary in consistency from very soft rubbers, i.e., materials which are soft at room temperature but will show retraction when relaxed, to those having a Mooney value (ML-4 212 F.) up to 100. The rubbery copolymers most frequently preferred have Mooney values in'the range between 5 and 50. They may be prepared by any polymerization methods known to the art, e.g., mass or emulsion polymerization. One convenient method for preparing these copolymers is by emulsion polymerization at temperatures in the range between 0 and 140 F. Recipes such as the iron pyrophosphatehydroperoxide, either sugar-free or containing sugar, the sulfoxylate, and the persulfate recipes are among those which are applicable. It is advantageous to polymerize to high conversion as the unreacted vinylpyridine monomer is diflicult to remove by stripping.

The conjugated dienes employed are those containing from 4 to carbon atoms per molecule and include 1,3- butadiene, isoprene,, 2-methyl-1,3-butadiene, and the like. Various alkoxy, such as methoxy and ethoxy and cyano derivatives of these conjugated dienes, are also applicable. Other dienes, such as phenylbutadiene; 2,3-dimethyl-l,3- hexadiene; 2-methoxy-3-ethylbutadiene; 2-ethoxy-3-ethyl- 1,3-hexadiene; 2-cyano-l,3-butadiene are also applicable.

Instead of using a single conjugated diene, a mixture of conjugated dienes can be employed. Thus, a mixture of 1,3-butadiene and isoprene can be employed as the conjugated diene portion of the monomer system.

The polymerizable heterocyclic nitrogen bases which are applicable for the production of the polymeric materials are those of the pyridine, quinoline, and isoquinoline series which are copolymerizable with a conjugated diene and contain one, and only one B! CH2=- substituent wherein R is either hydrogen or a methyl group. That is, the substituent is either a vinyl or an alpha-methylvinyl (isopropenyl) group. Of these, the compounds of the pyridine series are of the greatest interest commercially at present. Various substituted derivatives are also applicable but the total number of carbon atoms in the groups attached to the carbon atoms of the heterocyclic nucleus should not be greater than 15 because the polymerization rate decreases somewhat with increasing size of the alkyl group. Compounds where the alkyl substituents are methyl and/or ethyl are available commercially.

These heterocyclic nitrogen bases have the formula R a R R R R R R N N R R N Where R is selected from the group consisting of hydrogen, alkyl, vinyl, alpha-methylvinyl, alkoxy, halo, hydroxy, cyano, aryloxy, aryl, and combinations of these groups such as haloalkyl, alkylaryl, hydroxyaryl, and the like; one and only one of said groups being selected from the group consisting of vinyl and alpha-methylvinyl; and the total number of carbon atoms in the nuclear substituted groups being not greater than 15. Examples of such compounds are 2-vinylpyridine;

2-vinyl-5-ethylpyridine;

2-methyl-5 -vinylpyridine;

4-vinylpyridine; 2,3,4-trimethyl-5-vinylpyridine;

3,4,5 ,6-tetramethyl-2 vinylpyridine; 3-ethyl-5-vinylpyridine; 2,6-diethyl-4-vinylpyridine; 2-isopropyl-4-nonyl-5-vinylpyridine; Z-methyl-S-undecyl-3-vinylpyridine; 2,4-dimethyl-5,6-dipentyl-3 -vinylpyridine; 2-decyl-5-(alpha-methylvinyl) pyridine; 2-vinyl-3-methyl-S-ethylpyridine; 2-methoxy-4-chloro-6-vinylpyridine; 3-vinyl-5-ethoxypyridine; 2-vinyl-4,5-dichloropyridine; 2-(alpha-methylvinyl)-4-hydroxy-6-cyanopyridine; 2-vinyl-4-phenoxy-5-metl1ylpyridine;

2-cyano-5-(alpha-methylvinyl) pyridine; 3-vinyl-5-phenylpyridine; 2- para-methylphenyl) -3 -vinyl-4-methy1pyridine; 3-viny1-5- (hydroxyphenyl) -pyridine; 2-vinylquinoline; 2-vinyl-4-ethylquinoline; 3-vinyl-6,7-di-n-propylquinoline; 2-methyl-4-nonyl-6-vinylpyridine; 4-(alpha-methylvinyl)-8-dodecylquinoline; 3-viny1isoquinoline; l,6-dimethyl-3-vinylisoquinoline; 2-vinyl-4-benzylquinoline; 3-vinyl-5-chloroethylquinoline-3-vinyl-5,6-dichloroisoquinoline; 2-vinyl-6-ethoxy-7-methylquinoline; 3-viny1-6-hydroxymethylisoquinoline; and the like.

Another rubbery polymer which can be employed in the binder of the solid propellant composition of this invention is a copolymer of 1,3-butadiene with styrene.

Such copolymers are commonly known in the art as GR-S rubbers. Said GR-S rubbers can be prepared by any of the well known methods employing well known recipes. Any of the well known GR-S rubbers containing from 1 to 2 and up to about 25 parts of styrene can be used in the practice of the invention. The GR-S rubber designated at 1505 is one preferred copolymer for use in the practice of theinvention. GR-S 1505 can be prepared by copolymerizing 1,3-butadiene with styrene at 41 F. using a sugar free, iron activated, rosin-acid emulsified system. A charge weight ratio of butadiene to styrene is 90/10 and the polymerization is allowed to go to approximately 52 percent completion. The copolymer is then salt acid coagulated and usually has a mean raw Mooney value (ML-4) of about 40. Said copolymers usually have a bound styrene content of about 8 weight percent. Further details regarding the preparation of GR-S rubbers can be found in Industrial and Engineering Chemistry, 40, pages 769 to 777 (1948), and United States Patents 2,583,277; 2,595,892; 2,609,362; 2,614,100; 2,647,109; and 2,665,269.

The binder contains rubbery polymers of the type hereinbefore described and, in addition, there can be present one or more reinforcing agents, plasticizers, wetting agents, and antioxidants. Other ingredients which are employed for sulfur vulcanization include a vulcanization accelerator, a vulcanizing agent, such as sulfur, and an accelerator activator, such as zinc oxide. The finished binder usually contains various compounding ingredients. Thus, it will be understood that herein and in the claims, unless otherwise specified, the term binder is employed generically and includes various conventional compounding ingredients. The binder content of the base propellant composition will usually range from to 40 percent by weight. A commonly preferred range for said binder content is from 5 to 25 weight percent.

The copolymer comprising a conjugated diene and a polymerizable heterocyclic nitrogen base can also be cured by a quaternization reaction by incorporating therein a quaternizing agent and subjecting the resulting mixture to quaternizing conditions of temperature. Suitable quaternizing agents include alkyl halides such as methyl iodide and methyl bromide; alkylene halides such as methylene iodide and ethylene bromide; substituted alkanes such as chloroform and bromoform; alkyl sulfates such as methyl sulfate; and various substituted arornatic compounds such as benzoyl chloride, methyl benzene sulfonate, benzo-trichloride, hexachloro-p-xylene, benzal chloride, and the like.

The quaternizing temperature is usually in the range of 0 to 175 C., although temperatures outside this range can be used.

A general formulation for the binder component of the propellant composition of the invention is as follows:

Parts by weight Rubber 100 Reinforcing agent 0-50 Plasticizer 0-100 Wetting agent 0-10 Antioxidant 0-3 vulcanization accelerator 0-5 Sulfur 0-2 Metal oxide 0-5 Quaternizing agent 0-25 be used. Materials Which provide a rubber having good low temperature properties are preferred. It is also frequently preferred that the plasticizers be oxygen-containing materials.

Wetting agents aid in deflocculating or dispersing the oxidizer. Aerosol OT (dioctyl ester of sodium sulfosuccinic acid), lecithin, and Duomeen C diacetate (the diacetate of trimethylenediamine substituted by a coconut oil product) are among the materials which are applicable.

Antioxidants which can be employed include Flexamine (physical mixture containing 65 percent of a complex diarylamine-ketone reaction product and 35 percent of N,N-diphenyl-p-phenylenediamine), phenyl betanaphthylamine, 2,2-methylene-bis(4-methyl-6-tert-butylphenol), and the like. Rubber antioxidants, in general, can be employed or, if desired, can be omitted.

Examples of vulcanization accelerators are those of the carbamate type, such as N,N-dimethyl-S-tert-butylsulfenyl dithiocarbamate and Butyl-Eight. Butyl-Eight is a rubber accelerator of the dithiocarbamate type supplied by the R. F. Vanderbilt Company and described in Handbook of Material Trade Names by Zimmerman and Lavine, 1953 edition, as a brown liquid; specific gravity 1.01; partially soluble in water and gasoline; and soluble in acetone, alcohol, benzol, carbon disulfide and chloroform.

It is to be understood that each of the various types of compounding ingredients can be used singly or mixtures of various ingredients performing a certain function can be employed. It is sometimes preferred, for example, to use mixtures of plasticizers rather than a single material.

Oxidizers which are applicable in the solid propellant compositions of the invention are ammonium perchlorate and the alkali metal perchlorates. As used herein, the term alkali metal includes sodium, potassium, lithium, cesium, and rubidium. Ammonium perchlorate is the presently preferred oxidizer. Mixtures of said oxidizers are also applicable. In the preparation of the solid rocket propellant compositions, the oxidizers are ground to a particle size preferably within the range between 20 and 200 microns average particle size. The most preferred particle size is from about 40 to about 60 microns. The amount of oxidizer used is a major amount of the total composition and is usually within the range of about 60 to about weight percent of the base propellant, i.e.,

binder plus oxidizer. A commonly preferred range for said oxidizer content is from 75 to 95 weight percent.

Finely divided high energy additives can also be included in the propellant compositions of the invention. Examples of suitable high energy additives, include, among others, the following: aluminum, boron, magnesium, iron, beryllium, lithium, alloys of aluminum, alloys of magnesium, and mixtures thereof. It is preferred that said finely divided high energy additives have a particle size less than 50 microns, more preferably less than 20 microns, and still more preferably, less than 10 microns. Said high energy additives can be used in amounts of from to weight percent of the base propellant. 'In some instances greater amounts can be used.

The various ingredients in the propellant composition can be mixed on a roll mill or an internal mixer such as a Banbury or a Baker-Perkins dispersion blade mixer can be employed. The binder forms a continuous phase in the propellant with the oxidant as the discontinuous phase. One procedure for blending the propellant ingredients utilizes a stepwise addition of oxidizer ingredient. The binder ingredients are mixed to form a binder mixture and the oxidizer ingredient, having the diamine dinitrate dry blended therewith, is then added to said binder mixture in increments, usually 3 to 5, but fewer or more can be used.

After the propellant composition has been formulated as indicated above, or by any other suitable mixing technique, rocket grains can be formed by extrusion, compression molding, or injection molding, utilizing techniques known to those skilled in the art. The grain can be cured by heating. The curing temperature will generally be in the range between 70 and 250 F., preferably between 170 and 200 F. The curing time must be long enough to give required creep resistance and other mechanical properties in the propellant. The time will generally range from around three hours, when the higher curing temperatures are employed, to seven days when curing is effected at lower temperatures.

The following examples will serve to further illustrate the invention.

EXAMPLE I A 1,3-butadiene/2-methyl-5-vinylpyridine rubbery copolymer was prepared by emulsion polymerization at 41 F. in accordance with the following recipe:

1 Fifty-five runs were made using the above polymerization recipe. The latex was masterbatched with 19.5 parts of Philblack A (a trademark of Phillips Petroleum Company for a low abrasion furnace carbon black) per 100 parts of rubber. The black masterbatch was then acid coagulated, washed with water, and dried. The average conversion for these 55 runs was 85 percent in 17.0 hours. The amount of modifier used in each run was in the range of 0.60 to 0.80 part by weight.

3 Based on 100 parts by weight of rubber.

Two and one-half parts by weight per 100 parts by weight of rubber of said low abrasion furnace carbon black was milled into the rubber prepared as described above. This increased the amount of carbon black present to 22 parts/100 parts of rubber. Three parts by weight per 100 parts by weight of rubber of Flexamine, a physical mixture containing 65% of a complex diarylamine-ketone reaction product and 35% of N,N-diphenylp-phenylene-diamine, was also milled into said copolymer.

The thus prepared rubber masterbatch was used to prepare a binder having the composition set forth in Table I below. Said binder was prepared by mixing said masterbatch and other ingredients in a Baker-Perkins mixer. Mixing was continued until a uniform binder composition was obtained.

Table I Parts by weight Copolymer 100 Carbon black 22 Phenyl-beta-naphthylamine 1.75 Liquid polybutadiene 20 Butyl Eight 1 2 Sulfur 1.75 Zinc oxide 3 Magnesium oxide 5 Flexamine 2 3 Activated dithiocarbamate accelerator. 2 65% diarylamine-ketone reaction product, 35% diphenylp-phenylenediamine.

The liquid polybutadiene employed in said binder composition was prepared by mass polymerization using finely divided sodium as the catalyst. Said polybutadiene had the following properties:

Specific gravity, 60/60 F. Density at 60 F., lbs/gal. 7.5 Refractive index, n 1.5174 Iodine number 365-385 Ash, wt. percent 0.05 Color, Gardner 11 Volatile material, wt. percent 1.0 Saybolt Furol viscosity at 100 F 25'00 Propellant compositions containing the above binder in amounts of 15 parts by weight and ammonium perchlorate oxidizer in amounts of parts by weight, and with and without N,N,N',N'-tetramethyl-1,3-diaminobutane dinitrate incorporated therein, were prepared in the following manner. First, equal portions of said binder and said oxidizer were mixed in a Baker-Perkins mixer. Portions of the resulting mixture were then blended with (a) additional oxidizer to bring the amount of oxidizer up to the desired amount or (b) with additional oxidizer and said amine dinitrate to give the propellant compositions shown in Table II below.

The uniform blends thus produced were extruded into strands having a diameter of inch. Said strands were cut into sections approximately seven inches in length. Said strand sections were restricted on all surfaces except on one end, so as to prevent burning except on said one end, and then cured for 24 hours at a temperature of approximately 180 F. preparatory to determining burning rates.

Said burning rates were determined by placing the cured, restricted strand sections in a bomb and then pressuring the bomb to the desired pressure with nitrogen. The bomb was then placed in a temperature bath maintained at 70 F. The strands were then ignited and the time required for the propellant to burn between two fusible wires spaced a known distance apart was recorded. The burning rate was then calculated in inches per second. The results of said burning rate tests are given in Table H below.

Table II Burning rate, in./see. at Amine a pressure, p.s.i.g. ofdinitrate. amount; 1

Propellant N o.

1 Parts by weight per parts by weight of base propellant containing 85 parts of oxidizer and 15 parts of binder.

The ammonium perchlorate used in the propellant compositions of Table II above was a 70-30 mixture of two finely ground products having a weight average particle size of 74 and 15 microns, respectively. Three additional propellant compositions were prepared as described above for propellants 1 and 2 except that the ammonium perchlorate oxidizer used was a 70-30 mixture of two finely ground products having a weight average particle size of 210 and 40 microns, respectively. Results of burning rate tests on said last mentioned three propellants are given in Table HI below.

1 Parts by weight per 100 parts by weight of base propellant containing 85 parts of oxidizer and 15 parts of binder.

The results of the above tests demonstrate that the amine dinitrates of the invention can be effectively utilized to effect a reduction in burning rate of solid propellants containing a perchlorate oxidizer component.

As will be apparent to those skilled in the art, various other modifications of the invention can be made or followed in view of the above disclosure without departing from the spirit and scope of said invention.

I claim:

1. A propellant composition comprising from 60 to 95 weight percent of an oxidizer component selected from the group consisting of ammonium perchlorate and the alkali metal perchlorates, and from 5 to 40 weight percent of a binder component comprising a rubbery material selected from the group consisting of natural rubber and synthetic rubbery polymers; and from 1.0 to 20 parts by weight per 100 parts by weight of the total amount of said oxidizer component plus said binder component of a diamine dinitrate characterized by the structural formula i) n k R NO; NO; R

wherein: R is selected from the group consisting of alkylene and alkenylene groups containing from 2 to 14 carbon atoms; R is an alkyl group containing from 1 to 4 carbon atoms, which alkyl groups can be alike and unlike; and wherein the total number of carbon atoms in the molecule does not exceed 18.

2. A propellant composition according to claim 1 wherein said oxidizer component is ammonium perchlorate.

3. A propellant composition according to claim 1 wherein said rubbery material is natural rubber.

4. A propellant composition according to claim 1 wherein said rubbery material is a copolymer prepared by copolymerizing a conjugated diene containing from 4 to carbon atoms with at least one substituted heterocyclic nitrogen base selected from the group consisting of pyridine, quinoline, alkyl substituted pyridine and alkyl substituted quinoline wherein the total number of carbon atoms in the nuclear alkyl substituents is not more than 15 and wherein R is selected from the group consisting of a hydrogen atom and a methyl radical.

5. A propellant composition according to claim 4 wherein said copolymer is a copolymer of 1,3-butadiene with 2-methy1-5-vinylpyridine.

6. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N',N'-tetramethyl- 1,3-diaminobutane dinitrate.

7. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N,N'-tetramethyl- 1,6-diaminohexane dinitrate.

8. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N,N-tetramethyll,4-diamino-2,3-dimethylbutane dinitrate.

9. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N,N'-tetramethyl- 1,3-diamino-2,2-dimethylpropane dinitrate.

10. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N,N'-tetramethyl- 1,4-diaminobuta-ne dinitrate.

11. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N,N'-tetraethyl- 1,3-diaminobutane dinitrate.

12. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N,N,N'-tetramethyl- 1,3-diaminopropane dinitrate.

13. A propellant composition according to claim 1 wherein said diamine dinitrate is N,N-dimethyl-N',N-diethyl-1,3-diaminobutane dinitrate.

14. A propellant composition according to claim 1 wherein: said oxidizer component is ammonium perchlorate; said rubbery material is a copolymer prepared by copolymerizing a conjugated diene containing from 4 to 10 carbon atoms with at least one substituted heterocyclic nitrogen base selected from the group consisting of pyridine, quinoline, alkyl substituted pyridine and alkyl substituted quinoline wherein the total number of carbon atoms in the nuclear alkyl substituents is not more than 15 and wherein R is selected from the group consisting of a hydrogen atom and a methyl radical; and. said amine dinitrate is N,N,N',N'-tetramethyl-1,3-diaminobutane dinitrate.

15. A propellent composition according to claim 14 wherein said copolymer is a copolymer of 1,3-butadiene with Z-methyl-S-vinylpyridine.

16. A propellant composition according to claim 1 wherein said oxidizer component is ammonium perchlorate and said rubbery material is a copolymer of l,3- butadeine with 2-rnethyl-5-vinylpyridine.

17. A propellant composition according to claim 1 wherein said rubbery material is a copolymer of 1,3-butadiene with Z-methyl-S-vinylpyridine and said diamine dinitrate is N,N,N',N'-tetramethyl-1,3-diaminobutane dinitrate.

18. A propellant composition according to claim 1 wherein the amount of said diamine dinitrate is within the range of 0.2 to 5 parts by weight per parts by weight of the total amount of said oxidizer component plus said binder component.

References Cited in the file of this patent V UNITED STATES PATENTS 2,159,234 Taylor et a1 May 23, 1939 2,406,572 Voge Aug. 27, 1946 2,877,504 Fox Mar. 17, 1959 FOREIGN PATENTS 655,585 Great Britain July 25, 1951 OTHER REFERENCES Chem. and Eng. News, Oct. 7, 1957, pp. 62-3. 

1. A PROPELLANT COMPOSITION COMPRISING FROM 60 TO 95 WEIGHT PERCENT OF AN OXIDIZER COMPONENT SELECTED FROM THE GROUP CONSISTING OF AMMONIUM PERCHLORATE AND THE ALKALI METAL PERCHLORATES, AND FROM 5 TO 40 WEIGHT PERCENT OF A BINDER COMPONENT COMPRISING A RUBBERY MATERIAL SELECTED FROM THE GROUP CONSISTING OF NATURAL RUBBER AND SYNTHETIC RUBBERY POLYMERS; AND FROM 1.0 TO 20 PARTS BY WEIGHT PER 100 PARTS BY WEIGHT OF THE TOTAAL AMOUNT OF SAID OXIDIZER COMPONENT PLUS SAID BINDER COMPONENT OF A DIAMIONE DINITRATE CHARACTERIZED BY THE STRUCTURAL FORMULA 